EP1880692A1

EP1880692A1 - Color variable lamp, especially for dental use

Info

Publication number: EP1880692A1
Application number: EP06425516A
Authority: EP
Inventors: Franco Castellini
Original assignee: Castellini SpA
Current assignee: Castellini SpA
Priority date: 2006-07-21
Filing date: 2006-07-21
Publication date: 2008-01-23

Abstract

A lamp, especially for dental use, comprises: an external casing (1) mounting a light source (2) that generates rays of light in a certain wavelength range; means (3) for directing the light rays generated by the light source (2) in the form of a predetermined beam (F) and towards a desired area; a surface (4) for protecting the front of the light source (2) and of the directing means (3), and through which the light beam (F) passes, to form an element for enclosing the front of the illuminating body or reflector together with the external casing (1); light filtering means (6) acting on the lamp (5) and designed to permit the emission of light radiation limited to predetermined wavelengths to avoid early polymerization of dental preparations; means (7) for enabling and disabling the filtering means (6), located on the lamp (5) and acting on the filtering means (6) when required.

Description

This invention relates to a lamp, especially a lamp for dental use.
At present, lamps for dental use, that is to say, lamps used by dentists / orthodontists to illuminate the treatment area, comprise a light source (usually a customary halogen lamp or even a plurality of LEDs), a reflector (in the case of a halogen lamp) or light channelling means (in the case of LEDs) and a front surface for protecting these two elements and through which the light beam can pass. This protecting surface acts as an enclosure for the lighting element, together with an external guard protecting all the parts of the lamp and the electrical contacts. The lamp is mounted on an articulated arm used to position it correctly with respect to the area to be illuminated.
This structure effectively illuminates the patient and eliminates spurious light sources that might disturb operators. Up to now, these lamps have been made in such a way that the emitted light rays covers the full wavelength spectrum of the light source: in some situations, however - and we refer in particular to dental restorations - this feature may be detrimental to the success of the restorative stage of the operation in the dental cavity.
During these operations, paste products are used to make composites for dental restoration.
The composites, after being placed, are hardened using an appropriate handpiece (a curing lamp) to accelerate the polymerizing process. The lamp handpiece emits a beam of light (usually blue) with a predetermined wavelength or predetermined (very limited) wavelength range acting as a catalyst that accelerates the product polymerizing/hardening process.
Thus, when the lamp is switched on and directed at the treatment area (and, inevitably, also around it) in the patient's mouth, the light rays with the above mentioned wavelength may accelerate the composite polymerizing process within a space of time that does not follow the correct procedure required by the dental surgeon.
At present, the only way of avoiding this problem is to direct the lamp in such a way as not to directly irradiate the treatment area or to reduce the power of the light beam or even switch off the lamp altogether: this obviously reduces the illumination of the treatment area, making work more difficult for the dental surgeon and/or the dental assistant.
The Applicant, ever aware of the technical and practical requirements of dental surgery has therefore designed and made a lamp for dental use with the aim of allowing the patient's treatment area to be correctly illuminated without affecting the polymerizing processes of dental composites.
In accordance with the invention, this aim is achieved by a lamp, especially a lamp for dental use, having the technical characteristics described in one or more of the appended claims.
The technical characteristics of the invention, with reference to the above aims, are clearly described in the claims below and its advantages are apparent from the detailed description which follows, with reference to the accompanying drawings which illustrate a preferred embodiment of the invention provided merely by way of example without restricting the scope of the inventive concept, and in which:

Figure 1 shows a lamp for dental use according to the present invention in a side view with some parts in cross section;
Figure 2 shows a second embodiment of a lamp for dental use according to the present invention in a schematic side view with some parts in cross section;
Figure 3 shows a third embodiment of a lamp for dental use according to the present invention in a schematic side view with some parts in cross section; .
Figure 4 shows a fourth embodiment of a lamp for dental use according to the present invention in a schematic side view with some parts in cross section;
Figures 5 and 6 are schematic side views showing a fifth embodiment of a lamp according to the invention in two different operating configurations;
Figures 7 and 8 are schematic side views, with some parts in cross section, showing a sixth embodiment of a lamp according to the invention;
Figures 9 and 10 are schematic side views, with some parts in cross section, showing, respectively, a seventh and an eighth embodiment of a lamp according to the invention.

With reference to the accompanying drawings, the lamp according to the invention, denoted in its entirety by the numeral 5, is used to illuminate the working area of a dental surgery and, in particular, is combined with a dental unit.
The lamp 5 essentially comprises the following parts:

an external casing 1 that mounts
a light source 2 (which may be a halogen lamp or, as we will see further on in this specification, a set of LEDs 25) that generates rays of light in a certain wavelength range and that is positioned in the vicinity of
means 3 for directing the light generated by the light source 2 in the form of a predetermined beam (indicated by the arrows F) and towards a desired area;
a surface 4 for protecting the front of the light source 2 and of the directing means 3, and through which the light beam F passes, to form an element for enclosing the front of the illuminating body or reflector together with the external casing 1.

As we will see further on in this specification, the light directing means 3 may consist of a reflective plate - in the case of a traditional halogen lamp - or individual lenses 3a - for each LED 25 present - which may be positioned inside the casing 1 (see Figure 7) or mounted directly on the protective surface 4 (see Figure 8) which may thus itself constitute the directing means.
As illustrated in Figures 1 to 3, the lamp 5 also comprises light filtering means 6 and means 7 for enabling and disabling the filtering means 6.
The light filtering means 6 act on the lamp 5 and permit the emission of light radiation limited to predetermined wavelengths.
By limited wavelength is meant that the light, normally white, is reduced to a colour mix including a small (insignificant) part of white and the colours which, as described in more detail below, do not have any effect on special treatments.
The means 7 for enabling and disabling the filtering means 6 may be positioned on the lamp 5 and act directly on the filtering means 6 when required.
More specifically, the light filtering means 6 may limit the emitted light beam to a wavelength range of between 500 and 700 nanometres.
Preferably, the light filtering means 6 can limit the emitted light beam to a wavelength range of between 570 and 650 nanometres.
For special working requirements, the light filtering means 6 can limit the emitted light beam to a wavelength range of between 585 and 645 nanometres, so as to obtain a light beam in the orange colour spectrum, or to a wavelength range of between 575 and 585 nanometres, so as to obtain a light beam in the yellow colour spectrum, thereby excluding wavelengths or frequencies that have a polymerizing effect.
In fact, the types of light emitted by the lamp, in the yellow - orange zones of the colour spectrum, are complementary to the blue light used for accelerating the polymerizing process of dental composites and, therefore, the light emitted by the lamp is substantially neutral with respect to the curing light.
At a constructional level, the filtering means 6 may be positioned on the casing 1 and act on the front surface 4 of the lamp 5 (see Figure 1).
Thus, as illustrated in Figure 1, the filtering means 6 may consist of a filtering screen 8 associated with the casing 1.
The filtering screen 8 is rolled up on a winding / unwinding roller 9 forming part of the above mentioned enabling / disabling means 7 and allowing the screen to be moved (for example manually, without limiting the scope of the invention) so as to cover or uncover the front surface 4 (see arrows F1) and to be attached securely to a fastening element 10, constituting the other part of the enabling / disabling means 7, positioned on the opposite surface of the casing 1.
Alternatively, the filtering means 6 may be positioned inside the casing 1 and act directly on the light source 2 (see Figures 2 and 3).
In this case, the filtering means 6 may consist of a rigid filtering cylinder 11 coaxial with the light source 2 and surrounding the light source 2 itself.
The cylinder 11 is attached to the enabling / disabling means 7 which, in this case, are designed to allow the cylinder 11 to slide (see arrows F2) between an idle position in which the cylinder 11 is away from the light source 2 (see Figure 2) and permits traditional white light to be emitted, and a filtering work position, in which the cylinder 11 surrounds the light source 2 (see Figure 3) and thus causes the light to be filtered to provide yellow - orange light.
The enabling / disabling means 7 may comprise an arm 12 for mounting the filtering cylinder 11 and attached at one end of it to the cylinder 11 itself.
At its other end, the arm 12 is connected to a slider knob 13 associated with the back of the casing 1. The knob 13 is in turn slidably coupled, coaxially, with a guide pin 14 in such a way as to enable the cylinder 11 to move from the idle position to the working position and vice versa.
Alternatively, the enabling / disabling means 7 may again comprise the arm 12 that mounts the filtering cylinder 11, the knob 13 and the sliding pin 14 but, unlike the embodiment described above, the assembly, in this case, is located at the centre of the front protective surface 4 from where it is possible to control the movements of the cylinder 11 from the idle position to the work position and vice versa.
Obviously, the sliding action of the knob 13 may be performed by hand or by motor-driven systems without limiting the scope of the invention.
Figure 4 shows a fourth embodiment of the filtering means 6 consisting of a rigid filtering screen 20 placed over the outside of the front protective surface 4.
The enabling / disabling means 7 are interposed between the filtering screen 20 and the front protective surface 4 and are of the releasable type so that the filtering screen 20 can be fitted and removed as required.
More specifically, the enabling / disabling means 7 consist of a plurality of elements 21 with magnetic properties (for example, magnets) located on the filtering screen 20 and designed to allow the latter to be attached securely to or detached from the front surface 4 which is fitted with similar elements 22 with magnetic properties.
Figures 9 and 10 show further embodiments of the lamp 5 structure illustrated in Figures 2 and 3.
In the embodiment shown in Figure 9, the means 7 for enabling / disabling the filtering cylinder 11 may comprise a lever 50 attached at one end to the cylinder 11 and hinged, at 50a, to a fixed block 51 positioned at the bottom of the casing 1.
A part 50b of the lever 50 extends past the hinge point 50a and protrudes from the casing 1 (for example, through a suitable slot 1f) in such a way as to provide a grip that can be actuated manually to slide the cylinder 11 from the idle position to the work position and vice versa (see arrows F50).
Similarly, in Figure 10, the means 7 for enabling / disabling the filtering cylinder 11 may comprise a lever 52 attached at one end to the cylinder 11 and connected, at 52a, to a slide 53 that is slidably coupled to a fixed block 54 positioned at the bottom of the casing 1.
In this case, too, a part 52b of the lever 52 extends past the connection point 52a and protrudes from the casing 1 (for example, through a suitable slot 1f) in such a way as to provide a grip that can be actuated manually to act on the slide 53 and thus cause the cylinder 11 to move from the idle position to the work position and vice versa (see arrows F52).
In Figures 5 and 6, on the other hand, the filtering means 6 may consist of a filtering cap 23 equipped with a pair of mounting arms 24 hinged, at C, to the casing 1 and constituting the enabling / disabling means 7 since they allow the filtering cap 23 to be rotated (see arrows F23) from an idle position in which the cap 23 is away from the front surface 4 (see Figure 5) and a filtering work position in which the cap 23 covers the front surface 4 (see Figure 6).
As illustrated in Figures 7 and 8 and as mentioned above, the light source 2 may consist of a plurality of LEDs 25 positioned inside the casing 1, each one of which is acted upon by respective means 3 for directing the light source of the related LED 25 (the above mentioned lenses 3a) in such a way as to form a beam of light F in a predetermined direction and towards a desired area. In this embodiment, the filtering means 6 comprise at least one of the LEDs 25a equipped with a filtering light source and controlled by the enabling / disabling means 7 acting, when required, on the filtering LED 25a itself when at least some of the remaining LEDs 25 present are enabled / disabled.
Obviously, the remaining LEDs 25 may be disabled totally or partially, depending on the type of filtering light beam F required: total filtering (by disabling all the remaining LEDs 25) or partial filtering by disabling only some of the remaining LEDs 25 so that the filtering effect is "lighter".
For better visibility, the filtering means 6 may comprise a predetermined set of the LEDs 25a inside the casing 1 all equipped with the filtering light source and all connected to the enabling / disabling means 7.
Each filtering LED 25a, may, for example, be made with an orange colouring so as to exclude the wavelengths that have a polymerizing effect.
Alternatively, each filtering LED 25a, may be made with a yellow colouring so as to exclude the wavelengths that have a potential polymerizing effect.
In the embodiment with LEDs, the enabling / disabling means 7 may comprise a lamp 5 control unit 26 (for example a switch) equipped with means 27 for selectively enabling / disabling the filtering LEDs 25a: in practice, an auxiliary switch 27a might be provided for turning the filtering LEDs on or off and simultaneously enabling / disabling some or all of the remaining LEDs, while the main switch 27b controls only the general lighting LEDs.
A lamp made in this way thus achieves the aforementioned aims thanks to the presence of the filtering means mounted directly on the lamp and enabled when required.
This solution allows the dental surgeon to change the wavelength of the light quickly and easily when a dental composite being used for restorative purposes needs to be hardened. This can be done without risk while keeping the area the surgeon is working on properly and optimally illuminated.
The unobtrusive structure of the filtering means and of the enabling / disabling means has obvious advantages both in terms of the overall attractive appearance of the lamp and in terms of its final cost.
It will be understood that the invention described may be useful in many industrial applications and may be modified and adapted in several ways without thereby departing from the scope of the inventive concept. Moreover, all the details of the invention may be substituted by technically equivalent elements.

Claims

A lamp, especially for dental use, of the type comprising at least:
- an external casing (1) that mounts

- a light source (2) that generates rays of light in a certain wavelength range and that is positioned in the vicinity of

- means (3) for directing the light generated by the light source (2) in the form of a predetermined beam (F) and towards a desired area; the lamp (5) being characterised in that it also comprises:

- light filtering means (6) acting on the lamp (5) and designed to permit the emission of light radiation limited to predetermined wavelengths;

- means (7) for enabling and disabling the filtering means (6) positioned on the lamp (5) and acting on the filtering means (6) when required.
The lamp according to claim 1, characterised in that the light filtering means (6) limit the emitted light beam to a wavelength range of between 500 and 700 nanometres.
The lamp according to claim 2, characterised in that the light filtering means (6) limit the emitted light beam to a wavelength range of between 570 and 650 nanometres.
The lamp according to claim 2, characterised in that the light filtering means (6) limit the emitted light beam to a wavelength range of between 585 and 645 nanometres, so as to obtain a light beam in the orange colour spectrum, thereby excluding wavelengths that have a polymerizing effect.
The lamp according to claim 2, characterised in that the light filtering means (6) limit the emitted light beam to a wavelength range of between 575 and 585 nanometres, so as to obtain a light beam in the yellow colour spectrum, thereby excluding wavelengths that have a polymerizing effect.
The lamp according to claim 1, comprising a surface (4) for protecting the front of the light source (2) and of the directing means (3), and through which the light beam (F) passes, to form an element for enclosing the front of the illuminating body or reflector together with the external casing (1), the lamp being characterised in that the filtering means (6) are positioned on the casing (1) and act on the front surface (4) of the lamp (5).
The lamp according to claim 1, characterised in that the filtering means (6) are positioned inside the casing (1) and act directly on the light source (2).
The lamp according to claims 1 and 6, characterised in that the filtering means (6) consist of a filtering screen (8) associated with the casing (1); the filtering screen (8) being rolled up on a winding / unwinding roller (9) forming part of the enabling / disabling means (7) and allowing the screen to be moved in such a way as to cover or uncover the front surface (4) and to be attached securely to a fastening element (10), constituting the other part of the enabling / disabling means (7), positioned on the opposite surface of the casing (1).
The lamp according to claims 1 and 7, characterised in that the filtering means (6) consist of a rigid filtering cylinder (11) coaxial with the light source (2) and surrounding the light source (2) itself; the cylinder (11) being attached to the enabling / disabling means (7) to allow the cylinder (11) to slide between an idle position in which the cylinder (11) is away from the light source (2) and a filtering work position, in which the cylinder (11) surrounds the light source (2).
The lamp according to claims 7 and 9, characterised in that the enabling / disabling means (7) comprise an arm (12) for mounting the filtering cylinder (11), attached at one end of it to the cylinder (11) and connected also to a slider knob (13) associated with the back of the casing (1); the knob (13) being slidably coupled, coaxially, with a guide pin (14) in such a way as to enable the cylinder (11) to move from the idle position to the working position and vice versa.
The lamp according to claims 7 and 9, characterised in that the enabling / disabling means (7) comprise an arm (12) for mounting the filtering cylinder (11), attached at one end of it to the cylinder (11) and connected also to a slider knob (13) that is associated, centrally, with a front protecting surface (4); the knob (13) being slidably coupled, coaxially, with a guide pin (14) in such a way as to enable the cylinder (11) to move from the idle position to the working position and vice versa.
The lamp according to claim 6, characterised in that the filtering means (6) consist of a rigid filtering screen (20) placed over the outside of the front protective surface (4); the enabling / disabling means (7) being interposed between the filtering screen (20) and the front protective surface (4) and being of the releasable type so that the filtering screen (20) can be fitted and removed as required.
The lamp according to claim 12, characterised in that the enabling / disabling means (7) consist of a plurality of elements (21) with magnetic properties located on the filtering screen (20) and designed to allow the latter to be attached securely to or detached from the front surface (4) which is fitted with similar elements (22) with magnetic properties.
The lamp according to claim 6, characterised in that the filtering means (6) consist of a filtering cap (23) equipped with a pair of mounting arms (24) hinged, at (C), to the casing (1) and constituting the enabling / disabling means (7) in such a way as to allow the filtering cap (23) to be rotated between an idle position in which the cap (23) is away from the front surface (4) and a filtering work position in which the cap (23) covers the front surface (4).
The lamp according to claim 1, where the light source (2) consists of a plurality of LEDs (25) positioned inside the casing (1), each one of which being acted upon by respective means (3) for directing the light source of the related LED (25) in such a way as to form a beam of light (F) in a predetermined direction and towards a desired area, characterised in that the filtering means (6) comprise at least one of the LEDs (25a) equipped with a filtering light source and controlled by the enabling / disabling means (7) acting, when required, on the filtering LED (25a) itself when at least some of the remaining LEDs (25) present are enabled / disabled.
The lamp according to claim 15, characterised in that the filtering means (6) comprise a predetermined set of the LEDs (25a) equipped with the filtering light source and connected to the enabling / disabling means (7).
The lamp according to claims 15 and 16, characterised in that each filtering LED (25a) is made with an orange colouring so as to exclude the wavelengths that have a polymerizing effect.
The lamp according to claims 15 and 16, characterised in that each filtering LED (25a) is made with a yellow colouring so as to exclude the wavelengths that have a polymerizing effect.
The lamp according to claims 15 and 18, characterised in that the enabling / disabling means (7) comprise a unit (26) for controlling the lamp (5) and equipped with means (27) for selectively enabling / disabling the filtering LEDs (25a).
The lamp according to claims 1, 7 and 9, characterised in that the means (7) for enabling / disabling the cylinder (11) comprise a lever (50) attached at one end to the cylinder (11) and hinged, at (50a), to a fixed block (51) positioned at the bottom of the casing (1); a part (50b) of the lever (50) extending past the hinge point (50a) and protruding from the casing (1) in such a way as to provide a grip that can be actuated manually to slide the cylinder (11) from the idle position to the work position and vice versa.
The lamp according to claims 1, 7 and 9, characterised in that the means (7) for enabling / disabling the cylinder (11) comprise a lever (52) attached at one end to the cylinder (11) and connected, at (52a) to a slide (53) that is slidably coupled to a fixed block (54) positioned at the bottom of the casing (1); a part (52b) of the lever (52) extending past the connection point (52a) and protruding from the casing (1) in such a way as to provide a grip that can be actuated manually to act on the slide (53) and thus cause the cylinder (11) to move from the idle position to the work position and vice versa.